[PATCH RFC v2 4/6] drm/msm/dpu: Fix slice_last_group_size calculation

[Jessica Zhang]

Correct the math for slice_last_group_size so that it matches the
calculations downstream.

Fixes: c110cfd1753e ("drm/msm/disp/dpu1: Add support for DSC")
Signed-off-by: Jessica Zhang <quic_jesszhan at quicinc.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov at linaro.org>
---
 drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc.c
index b952f7d2b7f5..9312a8d7fbd9 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_dsc.c
@@ -56,7 +56,11 @@ static void dpu_hw_dsc_config(struct dpu_hw_dsc *hw_dsc,
 	if (is_cmd_mode)
 		initial_lines += 1;
 
-	slice_last_group_size = 3 - (dsc->slice_width % 3);
+	slice_last_group_size = dsc->slice_width % 3;
+
+	if (slice_last_group_size == 0)
+		slice_last_group_size = 3;
+
 	data = (initial_lines << 20);
 	data |= ((slice_last_group_size - 1) << 18);
 	/* bpp is 6.4 format, 4 LSBs bits are for fractional part */

-- 
2.39.2